Certain current complications following ST elevation (STEMI) and non-ST elevation (NSTEMI) myocardial infarction (within the 28 day period) (I23) ICD-10-CM
The I23 code range covers certain current complications following st elevation (stemi) and non-st elevation (nstemi) myocardial infarction (within the 28 day period) with 10 ICD-10-CM diagnosis codes. 9 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
Codes in the I23 Range 10 codes · 9 billable
- I23 Certain current complications following ST elevation (STEMI) and non-ST elevation (NSTEMI) myocardial infarction (within the 28 day period)Non-billable
- I23.0 Hemopericardium as current complication following acute myocardial infarction
- I23.1 Atrial septal defect as current complication following acute myocardial infarction
- I23.2 Ventricular septal defect as current complication following acute myocardial infarction
- I23.3 Rupture of cardiac wall without hemopericardium as current complication following acute myocardial infarction
- I23.4 Rupture of chordae tendineae as current complication following acute myocardial infarction
- I23.5 Rupture of papillary muscle as current complication following acute myocardial infarction
- I23.6 Thrombosis of atrium, auricular appendage, and ventricle as current complications following acute myocardial infarction
- I23.7 Postinfarction angina
- I23.8 Other current complications following acute myocardial infarction
About the I23 Code Range
ICD-10 code I23 covers various complications occurring within 28 days after a heart attack, specifically ST elevation (STEMI) and non-ST elevation (NSTEMI) myocardial infarctions. These codes identify issues like heart wall rupture, blood clots, and valve damage that arise soon after the initial heart injury.
The codes in the I23 category are used to classify specific problems such as hemopericardium (I23.0), which means blood in the sac around the heart following a heart attack. Other examples include atrial septal defect (I23.1) and ventricular septal defect (I23.2), both referring to abnormal openings in the heart walls caused by infarction. Rupture of the cardiac wall (I23.3), rupture of chordae tendineae (I23.4), and papillary muscle rupture (I23.5) are critical mechanical failures leading to impaired heart function. The presence of thrombosis in the heart chambers (I23.6) indicates clot formation after the infarction. Post-infarction angina (I23.7), or chest pain after the attack, and other related complications such as mitral valve regurgitation and arrhythmias (I23.8) are also included. Using the ICD-10 code for post-myocardial infarction complications helps in accurate diagnosis, treatment planning, and reporting for these severe heart attack aftermaths.
Questions About This Page
How many billable codes are in the I23 range?
Of the 10 codes in this range, 9 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the I23 range classify?
The range classifies certain current complications following st elevation (stemi) and non-st elevation (nstemi) myocardial infarction (within the 28 day period). Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
